[MPlayer-dev-eng] Bluray playback

[compn]

On Mon, 7 Sep 2009 09:01:41 +0300, Jonathan Nell wrote:
>I'm working on an mplayer patch to allow for 'native' Bluray playback
>(I found it immensely annoying that there is no way to play Bluray
>discs in linux - well at least no straightforward way). I wanted to
>get your thoughts regarding a few issues:

there was some java app that could be used on linux to decrypt:
https://help.ubuntu.com/community/RestrictedFormats/BluRayAndHDDVD

>1) Firstly, is there any way such a patch could be accepted being that
>it will implement AACS (and eventually BD+) decrypting?

yes, we'd love to have bluray/hddvd support.

as long as it:
is clean (no cosmetics to current code)
is tested in valgrind for memleaks
passes review :)

please tell us the codepath you are working on , that way we can tell
you if its the right way. the best code will be reusable in
other projects (vlc, gstreamer, xine, ffmpeg, etc). it will also be
able to compile on other OS like bsd, mac os x, and windows.

reimar wrote up some guidelines on the ffmpeg summer of code wiki page
for an aacs implementation:

Specifications: http://www.aacsla.com/specifications/ 
DumpHD: http://forum.doom9.org/showthread.php?t=123111

"Most parts (BD-J, MKB, title key generation) probably do not belong
into FFmpeg, this should be discussed with us before submitting an
application possible solution: only implement "lowest" level (decode
given the correct title key) but implement CSS en- and decryption as
secondary goal"


>2) Even if the decryption algos themselves are not a problem, they
>rely on a bunch of crypto keys (look at the doom9 forum for more
>info). This means that either Processing Keys are taken from a
>'legitimate' player and included, or a list of Volume Unique Keys are
>included. Would the distribution of these keys be covered under fair
>use?

well, you can ask the eff about that one. my personal (non-lawyer)
opinion is yes. but you saw what happened when the first key was spread
around...

>3) Is there any way to apply the patch without the keys and then allow
>the user to provide keys from wherever if the want to watch Bluray
>discs?

it would be best for someone to include the keys, sending a
patch anonymously. mplayer was built for speed, having users go
searching the internet for keys is not fast at all.

>I juist don't think it's very fair that Linux users cannot view their
>legal discs (which they paid for) in their legal drives (which they
>paid for)! What are your thoughts?

i would submit the whole thing anonymously, much how decss was. dvdjon
was the only public name (out of three) on that code, and you see what
it got him. ffmpeg has some anonymous code already, so i dont see any
problem doing it that way.

the mplayer team does not like it when distros remove parts of mplayer
to appease some legal team. because then it comes down to a user who
says 'mplayer does not play X, mplayer sucks' when it is the fault of
the distro for removing X.

we would rather distros not package mplayer if they are going to
cripple it. it saves us time in debugging.

-compn